Having read all the comments and the like, I now feel absolutely no loyalty to the main Amateur manufacturers. I will abandon thoughts of using digital repeaters and purchase the cheapest units that function reasonably well no matter who makes them. Anyton, Maybe.

This is clearly a hot button issue for many hams, but let me throw out yet another aspect of this that just occurred to me. What about the convergence of Ham radio and Internet protocols?

I've been playing with HSMM-MESH (aka Broadband-Hamnet) recently, using a couple of re-flashed Linksys wireless routers and just last week did a demonstration of it for my ham club. HSMM-MESH has been called a "Swiss army knife" of disaster and improvised communications because these units form a high speed, self discovering, self advertising, self configuring, and fault tolerant mesh of IP nodes, with DNS support, that can be used to connect PCs to servers, they can provide a relay link between two isolated meshes, and can be used to transmit any digital data needed, such as video, audio, e-mail, web date, spreadsheets, basically anything that can be digitally represented. This is all done in the Ham portion of the 2.4 Ghz band, and as Ham devices, can use high gain antennas and power amplifiers to achieve substantially more distance than traditional wireless routers.

However, encryption is very common and even unavoidable when you're dealing with Internet Protocols. Web sites starting with https, or even using Putty to SSH to a Linux server are encrypted. While the underlying HSMM-MESH communications are unencrypted (and include the owner's call sign), on the surface, it would appear that any encrypted data (even from a video security camera) and consequently any secure Internet Protocol is forbidden on an HSMM-MESH mesh network by part 97 rules as they are "messages encoded for the purpose of obscuring their meaning". Is this a correct interpretation?

While my philosophy has been that encryption was a bad thing for Ham radio, if this interpretation is correct, I may have to re-think my beliefs on this.

We ought to keep in mind that encryption to purposely hide the transmitted information is what is not permitted--any encryption that has a publicly available key, published or common, IS permitted on the ham bands. I think that people are forgetting that one basic item of information--that critically affects any conversation/debate about encryption on our bands.

We ought to keep in mind that encryption to purposely hide the transmitted information is what is not permitted--any encryption that has a publicly available key, published or common, IS permitted on the ham bands. I think that people are forgetting that one basic item of information--that critically affects any conversation/debate about encryption on our bands.

Do you have approval in writing from the FCC Enforcement Bureau that agrees with your interpretation?

97.113 prohibited transmissionsmessages encoded for the purpose of obscuring their meaning

That implies that messages can be encoded as long as the purpose is not to obscure the meaning of the message. The FCC permits the use of digital protocols like PSK31 because the protocol information is publically available. They also permit 802.11 encryption for the purpose of preventing access to non-amateurs because the key is made available to any licensed amateur that wants it.

If I read the APCO P25 specification correctly, the encryption capability is built into the audio CODEC and is user selectable to enforce privacy. This plus a digital access code on each packet. The capability of user selected encryption can be somewhat of a problem for Part 97 certified equipment.

P25 can be set to run without encryption easily enough, but it can just as easily be set for encryption too.

97.113 prohibited transmissionsmessages encoded for the purpose of obscuring their meaning

That implies that messages can be encoded as long as the purpose is not to obscure the meaning of the message. The FCC permits the use of digital protocols like PSK31 because the protocol information is publically available. They also permit 802.11 encryption for the purpose of preventing access to non-amateurs because the key is made available to any licensed amateur that wants it.

I don't think that you can compare PSK31 to encryption only because PSK31 in itself is not an encryption algorithm. It is a communication protocol that is available in the "public domain". Any non-ham, with enough knowledge, can download the software and monitor amateur transmissions. No different than going to your local AES and buying a D* portable to monitor those digital transmissions.

But with regards to you turning around the words in the Rule, if you were not using encryption to obscure the meaning, then what are you going to use it for? Even if you attempt to "advertise" the algorithm, there is no minimum standard and a non-ham (including the FCC) to be able to retrieve this information in the public domain. If you did decide to go this way and if there was an enforcement action them you would probably have to argue that you were using Public-Key cryptography and not encryption in their pure definitions.

I do see where you going with this and I'm not totally writing it off.

If I read the APCO P25 specification correctly, the encryption capability is built into the audio CODEC and is user selectable to enforce privacy. This plus a digital access code on each packet. The capability of user selected encryption can be somewhat of a problem for Part 97 certified equipment.

P25 can be set to run without encryption easily enough, but it can just as easily be set for encryption too.

It takes additional hardware and requires the use of an encryption keyloader to operate encryption with P25. While P25 has the ability to "support" both AES and DES encryption, it its not as easy as flipping a switch and turning it on and off. If you don't have the required and matching hardware in all of the radios and matching algorithm keyloaded, it will not work.

In-short, it is very difficult to operate encryption in P25 and takes a lot of effort. Operating in the clear takes literally no effort at all.

So, if something needs to be encrypted. Why can't another service be used? Can't hams get a business band license, use the frequencies there while using encryption just to pass sensitive information to another ham using the business band license and frequencies? Use some other commercial band, perhaps even the HF Marine Band with the appropriate license and use encryption if it is allowed?

Speaking of other services, I suggest that hams also carry non ham radios like FRS and even CB radios in their 'go boxes and bags'. Not everyone you meet during an emergency will have a ham license. CB is still useful for communicating with truckers who are constantly watching road conditions and serve as an extra means of information. FRS radios can be given to anyone to serve to relay information in the field, search and rescue or just an extra set of eyes and ears.

As we all know, SSB CB radios can carry further then regular AM. Non hams can use SSB CB radio to communicate reliably 25 to 35 miles away and serve as an extra set of eyes and ears further away from the immediate area and relay information to a ham who can then relay that information out.

If you had a situation with an extended blackout due to a hurricane, tornado, snow or ice storm and the cell towers aren't working. Think Hurricane Sandy. . You can still keep in touch with family and relatives who live several miles across town even if they weren't licensed by using SSB CB with 12 volt car power.

Point being, just because it isn't allowed on ham radio doesn't mean were out of luck. It means we might have to go to other services and frequencies to fill those gaps.

"if you were not using encryption to obscure the meaning, then what are you going to use it for?"

The 802.11 guys are sharing the frequency with non-licensed WIFI users. They use the built-in encryption to prevent non-amateur users from accessing their licensed, hi-power nodes. They are not using the encryption to obscure the meaning, they are using it to prevent access by unlicensed users. All of the licensed users are given the encryption key. So far, the FCC has gone along with this interpretation.

Another case where encryption is permitted is satellite control links.

I didn't say that I think encryption should be allowed, I just said that according to Part 97, it was. There is an example of a reason that encryption--with a public key--could be used, such as keeping people that buy cheap radios to fool around with (no, I not referring to licensed ham operators) can be kept out of those communications. There may be other, just as compelling reasons too.

And, no--I'm not trying to begin another round of why those cheap radios should not be sold. Enough about that (maybe too much) has already been said.

The whole purpose of encryption, is to prevent others from seeing or hearing your data. So who exactly are we hiding our transmissions from if we encrypt? If you want to obfuscate your communications, stick with PGP encrypted email. Shouldn't it be that simple? The whole purpose of Amateur Radio is rendered moot if we start encrypting our communications....isn't it?

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